Understanding difficult research passages
Upload a paper and highlight difficult passages to get plain-language explanations and ask follow-up questions.
Free plan
The free plan includes unlimited highlight explanations with basic AI models. More advanced analysis, including specialized math and figure features, is paid.
Free tiers can restrict usage or features. Paid upgrades are separate.
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Perplexity
Search & research
Perplexity combines web search with conversational answers and source links, helping you investigate a question and then ask follow-ups. It is useful for orientation on unfamiliar topics and collecting starting points for further reading. Its free plan covers everyday searching, while advanced research and premium model access have much tighter restrictions.
Andi
Search & research
Andi combines conversational search with web results, giving you a direct answer and links to explore further. Its public search experience also supports reading, summarizing, and explaining material. It is a convenient option for people who want AI-assisted search without creating an account, with a separate product for developers using its API.
Ask Brave
Search & research
Ask Brave brings an AI conversation interface into Brave Search, combining synthesized answers with webpages and other search results. You can start from a normal search and continue in the Ask view. It works in any supported browser, so you can try the service without installing the Brave browser first.
Consensus
Search & research
Consensus searches academic literature and connects answers to published research papers. It is useful for exploring what studies say about a question, tracing citations, and comparing evidence across a field. Basic paper search is freely available, while deeper synthesis, study snapshots, and more intensive research modes have separate usage allowances.